# 5 Exponents or powers

As you saw earlier multiplication is a way to represent and quickly calculate repeated addition. What if you have repeated multiplication? For example, say you have 2 × 2 × 2 × 2. In this case, 2 is being multiplied by itself four times.

In mathematics this is written as 2^{4} and say ‘2 raised to the power 4’ or ‘2 to the power 4’. The 4 is superscripted (raised) and referred to as the exponent, power or index. This notation tells you to take the base, 2, and multiply it by itself four times. When the exponent is 2, you usually say ‘squared’ and, when the exponent is 3, you say ‘cubed’.

Usually you will use a calculator to work these out and in the next section you’ll look at how to do this.